Beginner's question about data plot

The data used for this plot is a series of 0's followed by a series of 1's, then back to 0's. I expected to see a 0-1-0 pulse shaped signal starting at around 15 minutes and ending just before 50 minutes, but instead I see a starting and trailing slope. What causes this behavior? The code is as simple as it gets:

figure(1), plot(time,Enable_d)

title('Signal Enabled')

xlabel('Time (min)')

[KALYAN ACHARJYA]

How you expected to switch from 1 to 0, in plot its connect both data points have you look at stem?

figure(1), stem(time,Enable_d)
title('Signal Enabled')
xlabel('Time (min)')

[Raimund Herberg]

stem and stairs show similar behavior - a pulse between 40 and 50 minutes. But the corresponding data is '0' from 0 minutes to 15 minutes, '1' from 15 minutes to 50 minutes, then again '0' from 50 minutes to 80 minutes.

Answer 1

[the cyclist]

Try this instead

plot(time,Enable_d,'.','MarkerSize',32)

This code will plot individual points, without a connecting line.

Answer 2

[Raimund Herberg]

We are not quite there - still a '1' signal gap between 15 minutes and 40 minutes

[the cyclist]

How do you expect MATLAB to "know" how to fill in the gap from 15 to 40? How can it know you want it to be 1 right after Time = 15, rather than 0, or 0.5, or 0.73245?

The answer is -- MATLAB can't know what to plot there unless to program it to.

Answer 3

[Raimund Herberg]

The data is only 0's and 1's, binary, nothing else.

'0's from 1 minutes to 15 minutes, '1's from 15 minutes to 50 minutes, then again '0's from 50 minutes to 80 minutes.

[the cyclist]

It seems pretty clear from the plot (using my answer) that you have no data between 15 minutes and 40 minutes, or before about 13 minutes or so. (You might want to make the MarkerSize a little bit smaller than the 32 I chose, to see the individual data points better.)

Can you upload the data in a *.mat file?

Also, you keep "answering" your question, rather than commenting on other answers, which will get very confusing (especially if people start upvoting some answers).

[Raimund Herberg]

You are 100% correct, there are gaps in the data, see the attached excel file.

I was recently assigned to check the sizeable data collection related to a mile-long script and tripped over a few things that were all along assumed to be ok. I extracted data that I was suspicious of and created with it the simple plot depicted at the beginning of this trail.

To my bad I did not compare data and the specific timeline side by side. Instead i just looked at the data and could not understand why the plot function created a slope between 15 minutes and 40 minutes. Beginner's mistake, not to be repeated. Your suggested solution "plot(time,Enable_d,'.','MarkerSize',32)" is right on. Many thanks!!!

And this interaction also taught me a lot about the plot function.

[Image Analyst]

Did stairs() like in my answer not work? Did you even try it?

[Raimund Herberg]

Yes, I tried it as well, works beautifully!

Thanks a lot for your support.

Answer 4

[Image Analyst]

To get a plot with sharp, not sloping, edges, use stairs() or bar().